Mateusz Mikuła

Depending on toolchain version you will end up with one of these Dwarf versions: 2, 4, 5 when targeting 32-bit mingw-w64. Toolchain used to build Rust is rather ancient one...

> One can even wonder if it would be possible to classify it as a GNU ld bug. IMO it's surely a bug in GNU ld but it's not clear...

LLVM has been relicensed to Apache 2.0 with LLVM exception.

Compiler Rt provides Apache-2.0 version of this function but in assembly: https://github.com/llvm-mirror/compiler-rt/blob/7a739a0dfb6d408c6d587e5c7b52abd89fc3fdd3/lib/builtins/riscv/mulsi3.S

@infinity0 Rust ships with C code compiled from `llvm-project` submodule, see https://github.com/rust-lang/rust/pull/60981/files Also see last line here: ``` $ rg "compiler_builtins" src/*/Cargo.toml src/liballoc/Cargo.toml 15:compiler_builtins = { version = "0.1.10", features...

@infinity0 look closely at https://github.com/rust-lang/rust/pull/60981/files#diff-fa9668c926a2788f7849514fe3ed66a9. It will enable `compiler-builtins-c` feature if `src/llvm-project/compiler-rt` path exists.

> Do you know of a good way to test (even manually) whether the optimised C versions are actually being used? I don't know the whole process here, sorry.

Run installation with `RUST_BACKTRACE=1` and post whole build log. Your current info doesn't tell anything relevant but I guess it's git2-rs/ssh2-rs again.

You need to install development openssl package on your system via its own package manager.

Now you need development version of `libssh` and probably `git`.